Smoking article

ABSTRACT

Described herein is a wrapper for wrapping an aerosolizable material, the wrapper including at least three layers, wherein the peripheral layers comprise paper and an intermediate layer comprises a non-combustible material, and wherein at least the intermediate layer and one of the peripheral layers are provided as a laminate structure.

PRIORITY CLAIM

The present application is a National Phase entry of PCT Application No. PCT/EP2018/081395, filed Nov. 15, 2018, which claims priority from GB Patent Application No. 1719521.5, filed Nov. 24, 2017, each of which is hereby fully incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to smoking articles and specifically, although not exclusively, to a wrapper for an aerosolizable material, an aerosol generating article comprising a wrapped aerosolizable material, and an aerosol generating assembly containing an aerosol generating article, the aerosol generating article comprising a wrapped aerosolizable material.

BACKGROUND

Smoking articles such as cigarettes, cigars and the like burn tobacco during use to create tobacco smoke. Alternatives to these types of articles, release compounds by heating without burning an aerosolizable material.

Apparatus is known that heats aerosolizable material to volatilize at least one component of the aerosolizable material, typically to form an aerosol which can be inhaled, without burning or combusting the aerosolizable material. Such apparatus is sometimes described as a “heat-not-burn” apparatus or a “tobacco heating product” (THP) or a “tobacco heating device” or similar. Various different arrangements for volatilizing at least one component of the aerosolizable material are known.

The material may be for example tobacco, other non-tobacco products or a combination, such as a blended mix, which may or may not contain nicotine.

SUMMARY

A first aspect of the disclosure provides a wrapper for wrapping an aerosolizable material, the wrapper comprising at least three layers, wherein the peripheral layers comprise paper and an intermediate layer comprises a non-combustible material, and wherein at least the intermediate layer and one of the peripheral layers are provided as a laminate structure.

The peripheral layers may be referred to herein as the “innermost” and “outermost” layers. This refers to their location when the material is wrapped around an aerosolizable material.

In one example, the laminate structure may comprise the intermediate layer and the peripheral layer which is disposed adjacent to the aerosolizable material in use (i.e. the innermost layer). This may then be circumscribed or wrapped by one or more further layers, wherein the peripheral layer of the composite structure comprises paper (i.e. the outermost layer).

In another example, the laminate structure comprises each of the peripheral layers and the intermediate layer.

In some cases, the non-combustible material comprises a metal foil. In some cases, the metal foil comprises aluminum .

In some examples, the wrapper comprises more than three layers. In some cases, the wrapper consists of three layers. In some cases, the wrapper may consist of a three layer laminate structure comprising the peripheral layers and the intermediate layer.

A second aspect of the disclosure provides an aerosol generating article, the aerosol generating article comprising an aerosolizable material and a wrapper according to the first aspect of the disclosure wrapped around the aerosolizable material.

In some examples, the aerosolizable material comprises tobacco.

In some examples, the aerosolizable material is a rod of aerosolizable material and the wrapper circumscribes at least the end of the rod that is distant from the user's mouth in use. In some cases, the wrapper circumscribes at least the rod over at least 25% of the rod length.

In some examples, the aerosol generating article may additionally a filter and/or a cooling element. In some cases, the cooling element may be arranged between the aerosolizable material and the filter. In some cases, the filter may be arranged between the aerosolizable material and the cooling element.

A further aspect of the disclosure provides an aerosol generating assembly, the assembly comprising a heater and an aerosol generating article according to the second aspect. In some cases, the aerosol generating assembly may be a tobacco heating product (also known as a heat not burn device).

A further aspect of the disclosure provides a system comprising an aerosol generating device and an aerosol generating article according to the second aspect.

A further aspect of the disclosure provides a process for making an aerosol generating article comprising wrapping an aerosolizable material in a wrapper according to the first aspect.

A further aspect of the disclosure provides a method of preventing a user igniting or burning an aerosolizable material in an aerosol generating article, the method comprising wrapping an aerosolizable material in a wrapper according to the first aspect.

To the extent that they are compatible, features of the disclosure described in the context of one aspect as explicitly disclosed in combination with each other aspect.

BRIEF DESCRIPTION OF THE FIGURES

Further features and advantages of the disclosure will become apparent from the following figures description of examples of the invention, given by way of example only and do not place any limitation on the scope of the claims.

FIG. 1 is a schematic diagram of a side view of an aerosol generating article according to an example of the disclosure.

FIG. 2 is a schematic diagram of a first end view of an aerosol generating article according to an example of the disclosure.

FIG. 3 is a schematic diagram of a first end view of a different aerosol generating article according to an example of the disclosure.

FIG. 4 is a schematic diagram of a side view of an aerosol generating article according to an example of the disclosure.

FIG. 5 is an exploded schematic diagram of a wrapper according to an example of the disclosure.

FIG. 6 is an exploded schematic diagram of a wrapper according to another example of the disclosure.

DETAILED DESCRIPTION

As used herein, the term “laminate structure” refers to a multi-layer structure in which the layers are fastened together to form a single body. The layers may be fastened with an adhesive, for example. In other examples, the layers may be fastened by static interaction. In other examples, the laminate structure might be formed by (partially) melting a first layer, contacting the first layer with a second layer and allowing the first layer to solidify. Any suitable mechanism for fastening the layers together including, but not limited to, the above examples, tying, sewing, screwing, nailing, bolting, hooking etc. may be employed to form the laminate structure.

In some cases, an adhesive may coat the surface of each layer. In other cases, an adhesive may be applied only to the periphery of the layers. In some cases, each layer in the laminate structure may be fastened to the adjacent layer(s). In some example laminate structures, the periphery of two layers may be fastened together with intermediate layers trapped in-between.

In one example of the wrapper, the laminate structure may comprise the intermediate layer and the peripheral layer which is disposed adjacent to the aerosolizable material in use (i.e. the innermost layer). This may then be circumscribed or wrapped by one or more further layers, wherein the peripheral layer of the composite structure comprises paper (i.e. the outermost layer). FIG. 6 is a schematic illustration of such an example. The laminate structure (indicated by dotted lines) includes a peripheral layer 501 and the intermediate layer 502. The wrapper additionally comprises peripheral layer 503, although this is not part of the laminate structure.

In another example, the laminate structure comprises each of the peripheral layers and the intermediate layer. That is, in one example, the laminate wrapper for wrapping an aerosolizable material comprises at least three layers, wherein the peripheral (i.e. the innermost and outermost) layers comprise paper and an intermediate layer comprises a non-combustible material. FIG. 5 is a schematic illustration of such an example. The laminate structure (indicated by dotted lines) includes the peripheral layers 501, 503 and the intermediate layer 502.

In some cases, the non-combustible material comprises a metal foil. In some cases, it may consist essentially of or consist of a metal foil. Suitably, the metal foil may comprise, essentially consist of or consist of an aluminum foil. The metal foil is a non-combustible material that can nevertheless act to conduct heat to the aerosolizable material in use.

In some cases, the metal foil may be less than about 100μm, 50μm, 20μm, 10μm or 8μm thick. In some cases, it may be more than about 1μm, 3μm or 5μm thick.

In some cases, the wrapper may be a laminate wrapping material that consists of three layers (i.e. only the innermost and outermost layers comprising paper and the intermediate non-combustible layer). In some cases, the wrapper may consist of a three layer laminate structure comprising the peripheral layers and the intermediate layer.

In some cases, the innermost and outermost layers of the wrapper are tobacco wrapping paper.

A consideration when preparing aerosol generating articles such as tobacco heating products is that they should not produce an acceptable smoking experience if combusted, so that the user is not minded to burn the aerosol generating article. This is because the formulation of the aerosolizable material is not configured for combustion (and the aerosol that results from combustion may be less suitable for inhalation than the aerosol that results from heating but not burning that aerosolizable material, or than the aerosol which results from combustion of traditional cigarettes).

The use of a non-combustible layer in the wrapper prevents the aerosol generating article from being burned and smoked as a conventional combustible cigarette.

As used herein, the phrase “non-combustible” refers to a material that will not ignite or burn at temperatures normally associated with lighting (igniting) or burning of tobacco.

Further, the use of a metal foil layer results in a wrapper that has a low porosity, reducing side stream air flow to the aerosolizable material. This further reduces the propensity to burn through limiting the oxygen levels at the aerosolizable material.

Moreover, the inventors established that having paper in the innermost and outermost layers of a laminate wrapper may be beneficial because the laminate surfaces then have a coefficient of friction of that paper. This means that the laminate wrapper can be more readily used in known cigarette manufacturing processes and machines. The laminate surfaces having a coefficient of friction equivalent to that of a cigarette paper allows the garniture belt of an aerosol generating article making machine to drive the laminate wrapper through the garniture during the aerosol generating article manufacturing process.

In some cases, the innermost layer may also comprise a flavorant, which is transferred to the aerosolizable material when wrapped around the aerosolizable material and heated. In some cases, the flavorant is impregnated into paper in the innermost layer. In some cases, the flavorant may comprise menthol.

The inventors established that having paper in the innermost layer of the laminate material may be beneficial because it can act as a flavor carrier.

In some cases, the paper in either or each of the innermost and outermost layers of the laminate may have a basis weight of at least about 10 g.m⁻², 15 g.m⁻², 20 g.m⁻² or 25 g.m⁻² to about 50 g.m⁻², 45 g.m⁻², 40 g.m⁻² or 35 g.m⁻². Paper having a density in this range has a low porosity, which further reduces the propensity to burn through limiting the oxygen levels at the aerosolizable material.

In some cases, the paper in either or each of the innermost and outermost layers of the wrapper may be treated with one or more burn-retardant substances.

In one example, the wrapper is a laminate structure that consists of:

-   -   (a) a middle layer of aluminum foil, which is 1.0-7μm, suitably         6.0-6.3μm thick; and     -   (b) two layers of paper either side of the foil. The paper         layers each have a basis weight of 25-35 g.m⁻².

In one example, the wrapper comprises a laminate structure that consists of:

-   -   (a) a layer of paper which has a basis weight of 25-35 g.m⁻² and         is arranged adjacent to the aerosolizable material when wrapped;         and     -   (b) a layer of aluminum foil, which is 1.0-7μm suitably         6.0-6.3μm thick.

In this example, the wrapper additionally comprises a second paper layer which is wrapped over the laminate in use, the second paper layer having a basis weight of 25-35 g.m⁻².

In some cases, the laminate material can be wound onto a bobbin core for use with standard cigarette makers that are fed from a single paper bobbin.

In some cases, one or more ventilation apertures may be formed in the wrapper. The ventilation apertures may provide airflow into the aerosol-generating article during use, the air forming part of the inhaled aerosol.

The laminate structure may be formed using any suitable lamination technique. In one example, the layers may be adhered together.

In some examples of the aerosol generating article described herein, at least part of the innermost layer is disposed in contact with the aerosolizable material.

In some cases, the aerosolizable material comprises tobacco. The tobacco may be any suitable solid tobacco, such as single grades or blends, cut rag or whole leaf, ground tobacco, tobacco fiber, cut tobacco, extruded tobacco, tobacco stem and/or reconstituted tobacco. The tobacco may be of any type including, but not limited to, Virginia and/or Burley and/or Oriental tobacco.

In some examples, the aerosolizable material may be a rod of aerosolizable material. As used herein, the term “rod” generally refers to an elongate body which may be any suitable shape for use in an aerosol generating assembly. In some cases, the rod is substantially cylindrical.

In some cases where the aerosolizable material is a rod of aerosolizable material, the wrapper circumscribes at least the end of the rod that is distant from the user's mouth in use (i.e. a distal-end rather than a mouth-end). This ensures that the non-combustible wrapper is disposed around the end of the rod which the user might try to ignite. In some cases, the laminate wrapper circumscribes the rod over at least 25% of the rod length. In some cases, the wrapper extends over at least 35%, 40%, 45% or 50% of the rod length. As more of the rod is circumscribed, burning of the rod is more difficult.

In some cases, the wrapper does not extend over the entire length of the rod of aerosolizable material, resulting in cost savings. In some cases, the laminate wrapper extends over less than about 85%, 80%, 75%, 70%, 65% or 60% of the rod length.

FIG. 1 illustrates an example aerosol generating article. The aerosol generating article 101 includes an aerosolizable material 103 which is wrapped by a wrapper 102. In this example, this wrapper extends from the distal-end of the aerosolizable material over approximately 50% of the distance to the mouth-end of the aerosolizable material. In some examples, the wrapper 102 comprises three layers, wherein the peripheral layers comprise paper and an intermediate layer comprises a non-combustible material. In some examples, one peripheral layer and the intermediate layer are provided as a laminate structure (see FIG. 6). In other examples, both peripheral layers and the intermediate layer are provided as a laminate structure (see FIG. 5).

Optionally, the wrapper may also be arranged over the distal-end of the aerosolizable material, so that the distal-end is completely enclosed in the wrapper. FIG. 2 illustrates an example in which the wrapper 102 is wrapped around the circumference of the aerosolizable material 103. The distal-end of the aerosol generating article 101 is not covered by the wrapper. FIG. 3 illustrates an alternative example of an aerosol generating article 101 in which the wrapper 102 completely encloses the distal-end of the aerosol generating article.

Examples of the aerosol generating article may additionally comprise a filter and/or a cooling element. In some cases, these additional components may not be circumscribed by all layers of the wrapper; instead, they may be circumscribed by a single layer of the wrapper which extends over a greater proportion of the aerosolizable material than the other layers. Suitably, the additional components may be circumscribed by only the outermost peripheral layer of the wrapper (which also circumscribes the aerosolizable material) or alternatively, by only the innermost peripheral layer of the wrapper.

For example, the mouth-end of the aerosolizable material may be provided adjacent to one or more of a cooling element and a filter. A cooling element, if present, allows vapor components to condense to form an aerosol and/or spaces the very hot parts of the apparatus from the user. A filter, if present, may remove components from the fluid flow, affecting the chemical composition of the inhaled aerosol.

FIG. 4 illustrates an example of an aerosol generating article 101 which includes, in addition to the features of FIG. 1, a cooling element 104, a filter 105 and a mouth-end tube 106. The cooling element 104 and filter 105, as illustrated, may be arranged between the mouth-end of the aerosolizable material 103 and the mouth-end tube 106, so that flow from the aerosolizable material 103 passes through the cooling element 104 and filter 105 (or vice versa if the filter is arranged before the cooling element in the flow) before reaching the user. Although the example in FIG. 4 illustrates a cooling element 104, a filter 105 and a mouth-end tube 106, one or more of these elements may be omitted in other examples.

In some examples, the mouth-end tube, if present, 106 may be formed of for example paper, for example in the form of a spirally wound paper tube, cellulose acetate, cardboard, crimped paper, such as crimped heat resistant paper or crimped parchment paper, and/or polymeric materials, such as low density polyethylene (LDPE), or some other suitable material. The mouth-end tube 106 may be a hollow tube. Such a hollow tube may provide a filtering function to filter volatilized aerosolizable material. The mouth-end tube 106 may be elongate, in order to be spaced from the very hot part(s) of the main apparatus (not shown) that heats the aerosolizable material.

In some examples, the filter 105, if present, may be a filter plug, and may be made, for example, from cellulose acetate.

In some cases, the cooling element 104, if present, may comprise a monolithic rod having first and second ends and comprising plural through holes extending between the first and second ends. The through holes may extend substantially parallel to the central longitudinal axis of the rod. The through holes of the cooling element 104 may be arranged generally radially of the element when viewed in lateral cross-section. That is, in an example, the element has internal walls which define the through holes and which have two main configurations, namely radial walls and central walls. The radial walls extend along radii of the cross-section of the element and the central walls are centered on the center of the cross-section of the element. The central walls in one example are circular, though other regular or irregular cross-sectional shapes may be used. Likewise, the cross-section of the element in one example is circular, though other regular or irregular cross-sectional shapes may be used.

In an example, the majority of the through holes have a hexagonal or generally hexagonal cross-sectional shape. In this example, the element has what might be termed a “honeycomb” structure when viewed from one end.

In some cases, the cooling element 104 may comprise a hollow tube which spaces the filter 105, if present, from the very hot part(s) of the main apparatus that heats the aerosolizable material. The cooling element 104 may be formed of for example paper, for example in the form of a spirally wound paper tube, cellulose acetate, cardboard, crimped paper, such as crimped heat resistant paper or crimped parchment paper, and polymeric materials, such as low density polyethylene (LDPE), or some other suitable material.

The cooling element 104, if present, may be substantially incompressible. It may be formed of a ceramic material, or of a polymer, for example a thermoplastic polymer, which may be an extrudable plastics material. In an example, the porosity of the element is in the range 60% to 75%. The porosity in this sense may be a measure of the percentage of the lateral cross-sectional area of the element occupied by the through holes. In an example, the porosity of the element is around 69% to 70%.

Other examples of aerosol-cooling element are disclosed in PCT/GB2015/051253, the entirety of which is hereby expressly incorporated by reference, in particular in FIGS. 1 to 8 and the description from page 8, line 11 to page 18, line 16.

In further examples, the cooling element 104 may be formed from a sheet material that is folded, crimped or pleated to form through holes. The sheet material may be made, for example, from metal such as aluminum; polymeric plastics material such as polyethylene, polypropylene, polyethylene terephthalate, or polyvinyl chloride; or paper.

In some examples, the cooling element 104 and the filter 105 may be held together by a wrapper paper to form an assembly. The assembly may then be joined to the aerosolizable material by a further wrapper which circumscribes the assembly and at least the mouth end of the aerosolizable material to form the aerosol generating article 101. In other examples, the aerosol generating article 101 is formed by wrapping the cooling element 104, the filter 105 and the aerosolizable material 103 effectively in one operation, with no separate tipping paper being provided for the cooling element and/or filter components (if present).

In some cases, one or more ventilation apertures may be formed in the aerosol-generating article. The ventilation apertures may provide airflow into the article during use which forms part of the inhaled aerosol. It may be desirable to reduce airflow over the distal-end of the article to reduce the propensity to burn, and so the apertures may be formed nearer to the mouth-end of the article than to the distal-end. For example, the ventilation apertures may be formed in the cooling element and/or filter, if present. Moreover, the ventilation holes may be formed in a part of the article that is not wrapped in the non-combustible material. The inventors have established that cutting the non-combustible material to form ventilation apertures may not be straightforward.

In use, in some cases, the aerosol generating article may be arranged at least partially within a heating device to form an aerosol generating assembly which heats the article to generate an aerosol without burning. In some other cases, the article may be provided in an assembly with a fuel source, such as a combustible fuel source or chemical heat source, which heats but does not burn the aerosolizable material.

The above examples are to be understood as illustrative examples of the disclosure. It is to be understood that any feature described in relation to any one example may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the examples, or any combination of any other of the examples. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims. 

1. A wrapper for wrapping an aerosolizable material, the wrapper comprising: at least three layers, wherein peripheral layers comprise paper and an intermediate layer comprises a non-combustible material, and wherein at least the intermediate layer and one of the peripheral layers are provided as a laminate structure.
 2. The wrapper according to claim 1, wherein the laminate structure comprises each of the peripheral layers and the intermediate layer.
 3. The wrapper according to claim 1, wherein the laminate structure comprises the intermediate layer and the peripheral layer which is disposed adjacent to the aerosolizable material in use.
 4. The wrapper according to claim 1, wherein the non-combustible material comprises a metal foil.
 5. The wrapper according to claim 4, wherein the metal foil comprises aluminum.
 6. The wrapper according to claim 1, wherein the wrapper consists of three layers.
 7. An aerosol generating article, the aerosol generating article comprising an aerosolizable material and the wrapper according to claim 1 wrapped around the aerosolizable material.
 8. The aerosol generating article according to claim 7, wherein the aerosolizable material comprises tobacco.
 9. The aerosol generating article according to claim 7, wherein the aerosolizable material is a rod of aerosolizable material, and the wrapper circumscribes at least an end of the rod that is distant from a mouth of a user in use.
 10. The aerosol generating article according to claim 9, wherein the wrapper circumscribes at least the rod over at least 25% of a length of the rod.
 11. The aerosol generating article according to claim 7, further comprising at least one of a filter or a cooling element.
 12. The aerosol generating article according to claim 11, wherein the aerosol generating article comprises the filter and the cooling element, and wherein the cooling element is arranged between the aerosolizable material and the filter.
 13. An aerosol generating assembly comprising the aerosol generating article according to claim 7 and a heater.
 14. The aerosol generating assembly according to claim 13, wherein the aerosol generating assembly is a tobacco heating product.
 15. The aerosol generating assembly according to claim 13, wherein the heater is a device into which the aerosol generating article is at least partially inserted in use.
 16. A system comprising an aerosol generating device and the aerosol generating article according to claim
 7. 17. A process for making an aerosol generating article comprising wrapping an aerosolizable material in the wrapper according to claim
 1. 18. A method of preventing a user lighting or igniting an aerosolizable material in an aerosol generating article, the method comprising wrapping an aerosolizable material in the wrapper according to claim
 1. 